The SRMAtlas is a compendium of targeted proteomics assays to detect and quantify proteins in complex proteome digests by mass spectrometry. It results from high-quality measurements of natural and synthetic peptides conducted on a triple quadrupole mass spectrometer, and is intended as a resource for selected/multiple reaction monitoring (SRM/MRM)-based proteomic workflows.

Publicly available today
The database contains SRM transitions from a variety of data sources, as summarized here.
The Human SRMAtlas derived from 166,174 human proteome peptides is now available. The database will soon be expanded to include substantial coverage of several important model organisms, as outlined below